<template lang="html">
  <!-- <el-menu default-active="1" id="nav-menu">
    <el-menu-item index="2"><router-link to="/secondcomponent" class="nav-link"><i class="el-icon-message"></i>导航二</router-link></el-menu-item>
     <el-menu-item index="2"><router-link to="/page2" class="nav-link"><i class="el-icon-message"></i>导航二</router-link></el-menu-item>
  </el-menu> -->
    <el-menu default-active="2" class="el-menu-vertical-demo" @open="handleOpen" @close="handleClose">
      <el-submenu index="1">
        <template slot="title"><i class="el-icon-message"></i>导航一</template>
        <el-menu-item-group>
          <template slot="title">分组一</template>
          <router-link to="/secondcomponent" class="nav-link"><el-menu-item index="1-1">导航二</el-menu-item></router-link>
          <router-link to="/page2" class="nav-link"><el-menu-item index="1-2">选项2</el-menu-item></router-link>
        </el-menu-item-group>
        <el-menu-item-group title="分组2">
          <router-link to="/table" class="nav-link"><el-menu-item index="2-1">表格</el-menu-item></router-link>
          <router-link to="/form" class="nav-link"><el-menu-item index="2-2">form表单</el-menu-item></router-link>
          <router-link to="/select" class="nav-link"><el-menu-item index="2-3">select</el-menu-item></router-link>
        </el-menu-item-group>
        <el-submenu index="1-4">
          <template slot="title">选项4</template>
          <router-link to="/page1" class="nav-link"><el-menu-item index="1-4-1">选项1</el-menu-item></router-link>
        </el-submenu>
      </el-submenu>
      <router-link to="/page1" class="nav-link"><el-menu-item index="2"><i class="el-icon-menu"></i>导航二</el-menu-item></router-link>
      <router-link to="/page3" class="nav-link"><el-menu-item index="3"><i class="el-icon-setting"></i>导航三</el-menu-item></router-link>
    </el-menu>
</template>
